The present invention relates to medical devices and pertains particularly to an improved cardiac cooling jacket.
Open heart surgery is carried out with the heart deprived of the flow of blood for at least a short period of time. It is desirable to reduce the metabolism of the heart during the surgery in order to reduce potential damage. A typical technique for reducing the metabolism is to reduce the temperature of the organ.
Various techniques have been used in the past for reducing the temperature of an organ during surgery. One of the preferred methods of reducing the temperature is to wrap the organ in a cooling jacket through which a cold fluid is circulating. An early example of a cooling jacket is disclosed in U.S. Pat. No. 4,154,245 entitled "Apparatus for Local Hypothermia". A later and preferred form of cooling jacket for heart surgery is disclosed in U.S. Pat. No. 4,071,056 granted Nov. 15, 1990, both of common assignment herewith.
While the current designs for cooling jackets have been satisfactory, they do have some drawbacks. One drawback of the current design is that under certain circumstances, they do not fully insulate the organ from the patients body. The usual procedure is to wrap the cooling jacket around the organ and rest it on the patients body. The current design frequently leaves an opening for direct contact of the organ with the patients body with a resulting transfer of heat from the body to the organ.
Therefore, there is a need for an improved cooling jacket that fully insulates the organ from the patients body.